Danny often helps me _____ my English and I help him to learn Chinese.
| A．on | B．about | C．with | D．in |
The rivers will become dirtier and dirtier ______ we take action to protect them.
| A．since | B．if |
| C．until | D．unless |
He is an honest boy. I have no reason to _______ what he said.
| A．hear | B．doubt |
| C．repeat | D．believe |
-- It will be my turn. I feel a little nervous. --________ You can make it!
| A．Congratulations! | B．Take it easy. |
| C．kook out! | D．Have a good time. |
-- What was Jim wearing at the party?
-- Nothing ________. He was in his usual shirt and jeans.
| A．special | B．simple |
| C．important | D．interesting |
—It's so late. Why not write the report tomorrow? —But I don't know _______. I can do it if not now.
| A．why | B．when |
| C．how | D．where |